Injection device and a method of changing a cartridge in the device
First Claim
1. An injection device comprising:
- a dose setting mechanism operable to set a desired dose, the dose setting mechanism comprising a dose setting member and a dose rod, the dose setting mechanism being adapted to be in;
a first position during normal operation of the injection device in which the dose setting member and the dose rod engage so that the dose rod moves along with the dose setting member, anda second position during cartridge change in which the dose setting member and the dose rod do not engage thereby allowing the dose setting member and the dose rod to move independently,a piston rod cooperating with the dose rod and adapted to cooperate with a piston in a cartridge in order to expel a dose of liquid from the cartridge,an injection mechanism operable to cause the piston rod and the piston to expel a previously set dose of liquid from the cartridge, anda cartridge holder for releasably holding a cartridge,wherein the cartridge holder is operatively connected to the dose rod in such a manner that when a cartridge is being inserted in the cartridge holder, the dose rod is caused to move along with the piston rod in an at least substantially axial direction, at least while the dose setting mechanism is moved from the second position to the first position.
1 Assignment
0 Petitions
Accused Products
Abstract
A refillable injection device (1) having a dose setting mechanism with a dose setting member (4) and a dose rod (11). The dose setting member and the dose rod engage during normal operation of the injection device, and they do not engage during change of cartridge. The dose setting member and the dose rod need to be moved into engagement when a new cartridge is inserted in the injection device. Thereby there is a risk that stress is build-up in the piston rod. In order to prevent this, the cartridge holder is operatively connected to the dose rod in such a manner that when a cartridge is being inserted in the cartridge holder, the dose rod is caused to move along with the piston rod in an axial direction, at least while the dose setting member and the dose rod are moved into engagement.
388 Citations
13 Claims
-
1. An injection device comprising:
-
a dose setting mechanism operable to set a desired dose, the dose setting mechanism comprising a dose setting member and a dose rod, the dose setting mechanism being adapted to be in; a first position during normal operation of the injection device in which the dose setting member and the dose rod engage so that the dose rod moves along with the dose setting member, and a second position during cartridge change in which the dose setting member and the dose rod do not engage thereby allowing the dose setting member and the dose rod to move independently, a piston rod cooperating with the dose rod and adapted to cooperate with a piston in a cartridge in order to expel a dose of liquid from the cartridge, an injection mechanism operable to cause the piston rod and the piston to expel a previously set dose of liquid from the cartridge, and a cartridge holder for releasably holding a cartridge, wherein the cartridge holder is operatively connected to the dose rod in such a manner that when a cartridge is being inserted in the cartridge holder, the dose rod is caused to move along with the piston rod in an at least substantially axial direction, at least while the dose setting mechanism is moved from the second position to the first position. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A method of changing a cartridge in an injection device, the injection device comprising a dose setting mechanism operable to set a desired dose, the dose setting mechanism comprising a dose setting member and a dose rod, the dose setting mechanism being adapted to be in:
-
a first position during normal operation in which the dose setting member and the dose rod engage so that the dose rod moves along with the dose setting member, and a second position during cartridge change in which the dose setting member and the dose rod do not engage thereby allowing the dose setting member and the dose rod to move independently, the injection device further comprising a piston rod cooperating with the dose rod and comprising a cartridge holder being connected to the dose rod, the method comprising; moving the cartridge holder holding a cartridge desired to be replaced in such a manner that the cartridge is accessible, and in such a manner that the dose setting mechanism is caused to move from the first position to the second position, removing the cartridge from the cartridge holder, inserting a new cartridge into the cartridge holder, moving the cartridge holder holding the new cartridge in such a manner that a piston rod of the injection device is moved along with a piston of the new cartridge, and moving, by the cartridge holder, the dose rod and the piston rod, the dose setting mechanism from the second position to the first position while causing the dose rod to move along with the piston rod in an at least substantially axial direction. - View Dependent Claims (13)
-
Specification